Main cast,
Detective Sergeant (later Detective Senior Sergeant[2]) Vic Maddern (Michael Pate), head of Matlock's C.I. (Criminal Investigation) Branch, who grew up in the Matlock district and is an accomplished bushman and career cop (apart from a spell in the army where he fought in Korea). Aged in his forties, Maddern is divorced and has two children (his wife Kay is moving out in the first episodes). Dedicated, with an authoritative personality and a direct approach to his work, Maddern is well respected in the town. Maddern is eventually shot and severely wounded in mountainous bushland while pursuing small-time cattle-duffers and is evacuated to Melbourne for treatment (episode 192, "Have A Good Weekend"). Dialogue in later episodes indicates that he is recovering from his wounds, but will probably be transferred to a Melbourne squad once out of hospital.
Senior Detective Alan Curtis (Grigor Taylor), aged in his mid-20s, who has just arrived in Matlock from Melbourne and is essentially a city boy, sent to his first country posting against his will. Curtis eventually adapts to country life, and his character and abilities develop as he becomes more experienced in his new situation. He is eventually promoted to Detective Sergeant and transferred back to Melbourne (episode 99, "Dingo Hunter").
Sergeant (later Senior Sergeant) Bert Kennedy (Vic Gordon), head of the Uniform Branch, an Englishman who migrated to Australia in 1950. Kennedy is thorough but also easy-going with a good sense of humour. Married to Nell (Natalie Raine), who is a very good cook, Kennedy enjoys the country life in Matlock so much that he has knocked back promotion to avoid moving to Melbourne.
Senior Constable Gary Hogan (Paul Cronin), about 30, a friendly, easy-going person who grew up in the country, and is always willing to help in whatever work is going, who performs a wide variety of duties but usually works as a highway patrolman. His motorcycle is equipped with a radio (callsign 'Solo One') - a rare case of dramatic licence by Crawfords (normally very faithful to police procedure), as police motorbikes at the time were not equipped with radios. The character also made an impact in another way, making motorcycle cops far more acceptable to the Australian public, which had previously seen them as "heavies and storm-trooper types". According to series producer Ian Jones, as a result men were applying to join the police so they could be a motorcycle cop like Gary Hogan In the final episode, "The Curse of the Bangarang Prince", Hogan is notified of a posting to the town of Emerald - the setting for his spinoff series Solo One.